starting unstyled B revisited.

Thank you to all that responded .Thanks James Howell for the pictures. My reference mark is covered up by Behlen Overdrive but assume its at 3 O'clock like others said.I moved the magneto in every position possible in the slot travel allowed and for some reason it didn't change the running backwards no matter what. I certainly noticed the change in impulse position to reference point each time we moved the mag. My son and I started that tractor 50 times with timing changed each time and it had the same characteristic of running backwards each time. What was noticed is the engine didn't run smooth all the way advanced and started harder when timing was all the way retarded or all the way advanced. I will try the suggestions given by Mr. Howell next. Otherwise I'm baffled.

Its possible the governor gear isn't in correct time with the cam gear and there isn't enough open slot adjustment on the mag to correct..

If allllllllll is correct, when the left piston is at TDC, and the flywheel is on the correct crank spline, and cam to crank is in timing, the flywheels LHI is at the 3 o clock mark (behind the Behlen) THE OPEN FEMALE DRIVE SLOT IN THE GOVENOR SHAFT END (where mag mates) SHOULD BE FLAT HORIZONTAL FORE AND AFT...........If not the governor may off time to the cam which can easily happen if govenor got lifted and not reinstalled right with the cam, you may be a tooth or two off.......

If when the left piston is at TDC the female slot in govenor shaft end isn't flat horizontal YOUR GOVENOR (to cam) IS OUT OF TIME or else cam isn't right to crank. Its more common the governor is out of time with cam.

To avoid too fast timing causing the flywheel to kick back you gotta get the start impulse timing to SNAP right at TDC.

If I couldn't see the cam and govenor timing marks I set it so the open slot was flat horizontal for n aft when left piston was at TDC

PS rotating mag in govenor housing affects BOTH start and run timing. If you adjust the rear lag angle that ONLY affects start/impulse timing PERHAPS THE LAG ANGLE ADJUSTEMNT IN THE REAR IS WAYYYYYYYYYYYY OFF ????????? Another possible cause of your problem !!!!!!!!!!

John T

My unstyled A has an overdrive also. Here's what I did to find TDC. Take out both sparkplugs, rotate the flywheel to get compression stroke on number one cylinder. Insert a screwdriver into the sparkplug hole until you feel the piston. When you are at TDC you can rock the flywheel back and forth and feel the piston change direction. Two pieces of advice for you. One- Be safe and use common sense and Two- Listen to John T his advice has helped me. Let us know the results.